Apparatus for winding wire coils on a toothed stack

ABSTRACT

A wire feed winding needle mounting support and a stack mounting support permit movement of the winding needle and a stack in at least three coordinate axis directions relative to each other. The supports may be formed on separate modules for variable angular orientation relative to each other. A number of motors control relative movement of the winding needle and stack along the three directions for winding selected teeth in the desired distribution. The invention provides as a basic component pliant bearing surface clamp members on either side of the row of teeth of a stack to be wound. A clamp mounting yoke and further motor means alternately move the pliant bearing surfaces toward and away from the row of teeth on either side between a clamp position and an open position. The winding wire filament is alternately clamped against one side of the row of teeth and then the other while the winding needle moves up and down and back and forth &#34;dancing&#34; over the row of teeth seating the wire in slots between teeth of the stack without itself passing between adjacent teeth through the slots. The winding wire is unclamped by releasing the pliant bearing surfaces on both sides of the row of teeth while shifting the stack and row of teeth relative to the winding needle to different slot and tooth locations.

TECHNICAL FIELD

This invention relates to a new winding apparatus and method for windingwire around selected teeth of a toothed or slotted iron core or stack.The invention is applicable to a variety of complex windings.

BACKGROUND ART

Complex stack or core windings are required for certain motor and sensorapplications. For example, the stator and rotor windings used in anglesensitive transformer resolvers require a complex distribution ofannular turns for measuring angles. Typically, a tapered distribution ofcopper turns on iron teeth is utilized.

For high resolution angle resolvers, the teeth of the stack are formedcorrespondingly closer together. At sufficiently high resolutions thehigh density of the teeth and narrowness of the slots prevent a wirefeed winding needle from passing through the slots between teeth to formthe turns of wire. Yet turns of wire must be wound at differentcontrolled depths on the teeth and with spans extending around differentnumbers of teeth. Furthermore, the turns may have to be formed withinthe small space defined by an annular stack with inwardly projectingteeth.

Conventional flying head core winding machines do not lend themselves toachieving such distributions. In particular, they are inapplicable toannular stack configurations having teeth extending radially inwardly.The typical single and double flier type core winding machines such as,for example, described in U.S. Pat. Nos. 3,973,738; 3,857,172;3,705,459; and 2,949,554 are adapted for winding around radiallyoutwardly projecting teeth only. Even with radially outwardly projectingteeth flying head machines generally wind only large spans of teeth andcannot wind turns of wire around single teeth or small spans.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide a stackwinding method and apparatus for automatically winding selected teeth ofa toothed or slotted stack with windings of tapered or other irregulardistributions of copper. In particular, the invention is adapted foraccurate placement of wire turns at selected specified depths on teethof a stack, for winding single teeth or small spans of teeth, and forwinding turns of wire at high density in small spaces.

Another object of the invention is to provide an inexpensive method andapparatus for automating the winding of complex distributions of copperon slotted and toothed stacks having high density teeth and narrowslots, particularly where a wire feed winding needle cannot pass throughthe slots between teeth.

A further object of the invention is to provide an automated method andapparatus for stack winding of slotted and toothed stacks of variedconfiguration including both linear and annular stack configurations andannular stacks having either radially inwardly projecting or radiallyoutwardly projecting teeth, or teeth arranged on axes skewed or angledrelative to the stack axis.

DISCLOSURE OF THE INVENTION

In order to accomplish these results the present invention provides astack winding apparatus using a wire feed winding needle of the hollowtype for feeding and winding wire around selected teeth of the stack orcore. According to the invention, the winding needle and stack aremounted on supports for movement relative to each other in threecoordinate axis directions.

According to the invention the needle, rather than passing through theslots between teeth, "dances" over the teeth in alignment with a slot,moving up from the base or other selected depth of the teeth, across theteeth and down on the other side thereby laying wire in a slot. Duringthis movement, the wire is held in place at the base or other selecteddepth of a slot on the side of the teeth by novel pushers or clamps ofpliant material.

The stack and winding needle then translate relative to each other alongthe row of teeth to another slot location. There, the winding needle"dances" back over to complete a turn. While laying the wire in thesecond slot by movement up, across the teeth and down, the wire is againretained in place at the base or other selected depth of the teeth by apliant pusher or clamp on the other side. Thus, according to theinvention the winding needle forms the turns of copper wire not bypassing through the slots but by "dancing" back and forth over the rowof teeth in alignment with slots.

This action is achieved by motion of the winding needle and stackrelative to each other in three mutually perpendicular coordinate axisdirection. A first direction is back and forth across the row of teethfrom one side to the other. A second direction is up and down parallelto the teeth, and a third direction is along the row of teeth.

For example, in one embodiment the winding needle mounting supportcomprises a swing plate mounted on an axle for rotational motion througha prescribed and limited arc. A translating needle carrier is furthermounted on the swing plate for imparting translational motion to thewinding needle relative to the swing plate. The needle carrier operatesby extending and retracting a needle mounting arm which extends beyondthe side of the swing plate.

The wire feed winding needle is mounted at the end of the needlemounting arm and therefore translates back and forth across a row ofteeth in the first coordinate axis direction upon rotational motion ofthe swing plate through the prescribed arc. In addition, extension andretraction of the needle arm by the needle carrier imparts translationalmotion up and down parallel with the slots to the winding needle in thesecond substantially orthogonal coordinate axis direction.

The iron stack or core to be wound is supported in a stack mountingplate constructed and arranged for imparting independent movement to thetoothed stack relative to the winding needle and needle mounting arm inyet a third coordinate axis direction generally along the row of teethof the stack. Thus, the row of teeth may be shifted left and rightrelative to the winding needle. Where the slotted stack is of annularconfiguration movement of the stack and row of teeth relative to thewinding needle is accomplished by rotating the stack in oppositeclockwise and counterclockwise rotational directions. The stack mountingplate positions the row of teeth of the stack or core at a locationbeneath or adjacent to the winding needle with the winding needle inalignment with a slot.

A number of motors may provide the relative movement between the stackand winding needle. For example, a first motor drives the needlemounting support for motion of the needle back and forth in the firstdirection across the stack to either side of the row of teeth. In oneembodiment this is accomplished by engaging the swing plate to move theswing plate back and forth through a prescribed arc. A second motordrives the needle carrier and needle mounting arm for extension andretraction for moving the winding needle up and down along the seconddirection parallel with the slots and teeth of the stack.

A third motor is coupled to the stack mounting plate for moving thestack itself and row of teeth right and left relative to the windingneedle in a third substantially orthogonal axial direction along the rowof teeth of the stack. For example, the third motor drives a worm gearwhich engages the geared periphery of a circular frame in the stackmounting plate for rotational motion of annual configuration stacks andcores.

However, a variety of arrangements and configurations may be constructedfor imparting relative motion between the winding needle and stack alongthree perpendicular coordinate axis directions. In a preferred form ofthe winding apparatus the winding needle and needle arm are mounted on afirst winding apparatus module which imparts motion to the windingneedle in the first and second orthogonal coordinate axis directions.The toothed stack is mounted on a second winding apparatus module formovement of the row of teeth relative to the winding needle in a thirdcoordinate axis direction. The modules are juxtaposed so that thewinding needle "dances" over the row of teeth without passing throughthe slots laying turns of wire according to the method of the inventionaround desired spans of teeth.

The invention further provides as a basic element wire clamps or pushersmade of pliant material such as rubber positioned on either side of therow of teeth of the stack. A clamp mounting support mounts the clampsfor movement toward and away from the row of teeth between a clampposition and an open position. In the clamp position the pliant bearingsurface of the clamp or pusher bears against a portion of one side ofthe row of teeth of the stack, conforming to the surface of any windingalready formed around selected teeth. As a result, the winding wirefilament and windings of wire already formed are held in place near thebase of a slot or at a desired depth while the winding needle "dances"over the row of teeth, moving relative to the stack back and forth or upand down seating windings of wire filament in selected slots. In theopen position when the pliant bearing surfaces of the clamps or pushersare withdrawn and released the stack and row of teeth or the windingneedle are moved in the third direction along the row of teeth relativeto each other for subsequently winding wire filament around teeth andthrough slots at further locations.

A feature and advantage of the winding wire pusher or clamp according tothe invention is that turns of wire can be held in place at any selecteddepth along the height of a tooth. The winding needle lays the wire atthe desired depth in a slot and the pusher holds it in place against atooth while the winding needle moves up and over the row of teeth to thecorrect depth on the other side of the row.

In the swing plate form of the invention a clamp yoke is formedcoaxially around the axle for independent rotational movement relativeto the axle. The clamp yoke is formed with first and second yoke armsextending on either side of the axle and swing plate. A clamp or pushermounting arm extends from each of the respective first and second yokearms in a direction parallel with the needle mounting arm. Each clamp orpusher comprises a member of pliable material such as rubber mountedrespectively on the clamp mounting arms. A fourth motor drives the clampyoke for imparting reciprocal rotational motion so that the pliantsurface of the clamps or pushers alternately extend back and forthbetween the clamp position and the open position. The stack mountingplate positions the stack and row of teeth at a location below oradjacent the winding needle and between the clamps or pushers supportedby the clamp yoke.

In a preferred form of the invention using first and second stackwinding apparatus modules, the pliant clamps or pushers and clamp armsextend from a rotatable shaft mounted from the second module for pushingand retracting the clamps between the clamp position and releaseposition. A feature and advantage of the two module winding apparatus isthat the first and second modules can be oriented at an angle relativeto each other for winding angled or skewed teeth as well as right angleteeth. Thus, the axes of the teeth and slots may be offset at an angleto the stack axis.

According to the stack winding method the present invention contemplatespositioning relative to each other at a first location the wire feedingwinding needle and a toothed stack to be wound. The wire is placed at adesired depth relative to the teeth and slots. The invention thenprovides for clamping the winding wire or filament from the windingneedle against one side of the row of teeth of the stack using thepliant surface of the clamp or pusher thereby holding the wire at thefirst location. At each such location, the winding needle is generallyaligned with a slot.

The invention then contemplates the steps of raising the winding needlefrom a position adjacent to the base of the row of teeth of the stack orother desired depth to a position above the row of teeth, moving thewinding needle from a position on one side of the row of teeth to aposition on the other side, and then lowering the winding needle to aposition adjacent to the base of the row of teeth or other desired depthso that wire is seated in the slot between teeth of the row. These stepsof raising the winding needle, moving it across the row, and thenlowering it on the other side all take place while clamping the windingwire against the row of teeth on the initial side at the desired wireturn location. Furthermore, the characterization used herein that thewinding needle "dances" over the row of teeth in laying turns of copperwire refers to these steps.

Further steps follow according to the invention of unclamping the wireon the one side by releasing the pliant surface of the clamp and movingthe stack and row of teeth relative to the winding needle to a secondlocation at which the winding needle is aligned with a slot.

A series of similar steps then follows on the other side by clamping thewire at a desired depth against the other side of the row of teeth withthe pliant surface of a clamp or pusher according to the invention andthen in sequence raising the winding needle from a position at thedesired depth to a position above the row of teeth, moving the windingneedle from the position on the other side of the row of teeth back to aposition on the initial side, and then lowering the winding needle tothe desired depth so that the wire is seated in another slot betweenteeth of the row, thereby completing a turn or partial turn of wire.

Finally the method provides for unclamping the wire on the other side byreleasing the pliant surface of the clamp or pusher and again moving thestack and row of teeth relative to the winding needle to anotherlocation. The foregoing steps by which the winding needle dances overthe row of teeth laying turns of wire are of course repeated accordingto a programmed sequence either manually or by the use of automatedmachinery and controls to complete windings around selected teeth in thedesired distribution pattern and configuration.

According to the preferred form of the invention the method isapplicable to stacks of annular configuration and the step of moving thestack and row of teeth relative to the winding needle is accomplished byreciprocal rotation of the stack in clockwise and counterclockwisedirections relative to the winding needle. In this respect the methodand apparatus of the invention are applicable to annular stacks or coreswhich are slotted or toothed around either the inner periphery orcircumference or the outer periphery or circumference, or on both sides.Furthermore, the invention is applicable to linear cores having rows ofteeth in linear or other noncircular configuration. The method permitswinding coils of different densities and numbers of turns, arounddifferent spans of teeth including a single tooth, and with accurateplacement along the depth of the teeth and slots.

Throughout the winding method specified tension is maintained on thewinding wire passing through the winding needle for achieving neat, wellplaced and taught turns of wire filament in each winding. Such a wiretensioning device or arrangements may be mounted on the stack mountingplate or other portion of the apparatus to achieve the desired tensionas the wire feeds to the winding needle. Other objects, features andadvantages of the present invention will become apparent in thefollowing specification and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view from the front of the stack winding machineaccording to the present invention.

FIG. 2 is a side view of the stack winding machine.

FIG. 3 is a plan view from above of the stack winding machine.

FIG. 4 is a detail fragmentary plan view from above looking at oppositeclamps or pushers, while FIGS. 4A and 4B are diagrammatic views fromabove showing the diagonally juxtaposed operative portions of the clampsor pushers according to the direction of movement of the stack or row ofteeth.

FIGS. 5A through 5I are diagrammatic views from above showing thesequence of steps for stack winding around selected teeth of a tooth orslotted stack according to the present invention.

FIG. 6 is a diagrammatic perspective view or flow diagram summarizingthe stack winding method according to the invention in a singleconsolidated diagram.

DESCRIPTION OF PREFERRED EXAMPLE EMBODIMENTS AND BEST MODE OF THEINVENTION

A stack winding machine or apparatus 10 according to the invention isillustrated in FIGS. 1-3. As there shown, winding wire or filament 11 isfed through a hollow wire feed winding needle 12 for winding in aselected pattern around the teeth 14 of slotted stack or core 15. In theembodiment of FIGS. 1-3 a stack or core 15 of annular configuration isshown. Furthermore, the annular stack 15 is slotted or toothed aroundits inner periphery or circumference. As is hereafter apparent, theinvention is applicable also to annular stacks slotted or toothed aroundthe outer periphery or circumference and to linear stacks having atleast a row of teeth.

The winding needle 12 is of the hollow type for feeding and winding wireheld under selected tension by a standard tensioning means or device,not shown, which may be mounted on the apparatus. The winding wire isdelivered through the tensioning device from a source not shown.

Winding needle 12 is mounted on the needle mounting arm 18 which extendsfrom the needle carrier 19 which in turn is mounted on and connected toa swing plate or needle mounting plate 20. The needle swing plate 20 ismounted for rotational movement on an axle 22. The swing plate 20undergoes reciprocal rotation through a prescribed arc and is driven inthis swinging or rotational movement by a first drive motor 24 whichrotates a gear element 25. The rotating gear 25 engages a rack 26mounted at the free end of swing plate 20 for rotational motion orswinging motion of swing plate 20 through a prescribed arc. As a resultof the swinging motion of plate 20 the winding needle 12 undergoestranslation back and forth across the row of teeth 12 from one side ofthe teeth to the other side in a first coordinate axis direction.

The needle carrier 19 from which extends the needle mounting arm 18includes a winding needle motor 19a which extends and retracts theneedle arm 18 by, for example, driving a conventional lead screw whichlifts needle arm 18 up and down on a threaded sleeve or nut forimparting up and down motion of the winding needle 12 in a secondcoordinate axis direction parallel to the slots between the selectedteeth 14 around which the wire is being wound.

The annular stack or core 15 is mounted for rotational movement in acircular frame or insert 28 in turn supported in a stack mounting plate30 positioned adjacent to the swing plate 20. The stack mounting plate30 is fixed in stationary postion while the circular frame or insert 28may rotate relative to the stack plate 30. In order to effect therotation of the stack 15 within the stack mounting plate 20 the circularframe or insert 28 is formed around its outer periphery with a gearedsurface 32.

A worm gear 34 external to the mounting plate 30 engages thecomplimentary surface 32 formed around the periphery of insert 28. Theworm gear may be formed on the axle 22 below the stack 15 and insert 28or on a separate axle 35 positioned at the top of stack mounting plate30 above the stack 15 and insert 28 as shown in FIG. 1. The worm gear 34which engages the complementary gears 32 of the insert 28 is driven by athird motor 38 which upon rotation translates or moves the row of teeth14 back and forth in the vicinity of winding needle 12 in a thirdcoordinate axis direction orthogonal to the first and second directions.A feature and advantage of this arrangement is that the stack may beshifted left or right as many teeth as desired for winding turns arounddifferent numbers of teeth, e.g. 1, 2, 3 teeth at a time, etc. Aftereach stack shift the winding needle is aligned with a slot when thestack stops.

Another basic element of the stack winding apparatus according to theinvention is a clamp yoke 40 fitted and mounted around axle 22 for freerotation relative to the axle. The clamp yoke 40 includes elongate yokearms 42 and 43 which extend on either side of the axle 22 and swingplate 20. A clamp or pusher block support arm 44 extends from each yokearm 42 and 43. A clamp, pusher, or block 45 made of resilient materialsuch as rubber is mounted at the end of the each of the clamp arms 44extending from the respective yoke arms 42 and 43. As shown in FIG. 3and also in more detail in FIG. 4, each clamp block 45 includes spacedapart clamping elements 45a and 45b spaced from each other a distancecorresponding to the spacing of the teeth 14 of the stack or core 15 tobe wound.

The fixed elements of the stack winding apparatus including stackmounting plate 30, motors 24, 48 and 38 and axle 22 are fixed andmounted to a side frame 60 shown in FIG. 3.

As is apparent in FIGS. 1-3 the stack mounting plate 30 positions thestack or core 15 to be wound at a location adjacent to swing plate 20 sothat the selected teeth at the row of teeth 14 to be wound arepositioned beneath or adjacent to winding needle 12 and between theclamp blocks 45. The clamp yoke 40 is driven for reciprocal rotationalmotion relative to the axle 22 by means of a fourth motor 48. Byrotational motion of clamp yoke 40 the clamp blocks or pushers 45 arealternately applied to and fro against a portion of the row of teeth 14of stack 15 between a clamp position and an open position. In the clampposition the resilient face 46 of clamp block 45 is applied against aportion of the side of the row of teeth and the resilient surface 46yields and conforms to the irregular surface on the side where previouswindings may have already been formed. In this manner, the winding wireis held securely against the side of the teeth for further windingoperations as hereafter described without injury or damage to the wire.

The clamping blocks or pushers 45 positioned on either side of the stackto be wound are shown in further detail in FIG. 4. It is noted that eachclamp block or pusher 45 of pliant material such as rubber includes twoclamp elements 45a and 45b which generally coincide with adjacentportions of the row of teeth 14 of the stack 15. During the windingoperation as hereafter described only one of the elements 45a or 45b oneither side is actually operative to secure the winding wire at thedesired location. Thus, only the diagonally opposite elements 45a and45b are operative according to the direction of translation anddirection of winding as shown in FIGS. 4A and 4B. The detailed sequenceof steps for stack winding according to the method of the presentinvention and the corresponding operation of the winding wire clamps orblocks are further elucidated with reference to FIGS. 5A through 5I.

At the outset of the winding operation the wire feed winding needle 12and toothed stack to be wound 15 are positioned relative to each otherto initiate the winding operation. In particular, the winding needle 12and toothed stack 15 are positioned relative to each other at a firstlocation as illustrated in FIG. 5B. At this location the winding wire isclamped against one side of the row of teeth 14 by the pliant bearingsurface 46 of clamp block or pliant member 45b which is moved into theclamping position as shown in FIG. 5C.

In the illustrated steps of FIG. 5 the stack 15 may represent either alinear stack or annular stack having a row of teeth 14 in a generallylinear sequence either as the straight row of a linear stack or as theportion of a row of teeth from the inner or outer periphery of anannular stack. While clamp block element 45b is in the clamp position,clamp element 45a on the opposite side of the row of teeth 14 is in theopen position. Furthermore, throughout the initial steps illustrated inFIGS. 5B and 5C the winding needle 12 is at a location on one side ofthe row of teeth adjacent to the base of the slots between the teeth 14for seating the winding wire 11 at the base of a slot.

After clamping as shown in FIG. 5C, the winding needle 12 is raisedupward in the second coordinate axis direction parallel to the directionof teeth as shown in FIG. 5D. While FIG. 5D has the same appearance asFIG. 5C because it is a plan view from above, it should be kept in mindthat the winding needle 12 is in a lower position adjacent to the baseof the slots between teeth 14 in FIG. 5C and in raised position abovethe teeth 14 in FIG. 5D.

In the next step according to the stack winding method the windingneedle 12 traverses across and over the row of teeth 14 from one side ofthe stack to the other side in the first coordinate axis direction whilethe winding wire 11 is clamped against the initial side of the row ofteeth 14. The needle then drops from the raised position above the rowof teeth 14 to a lower position adjacent the base of the slots andrespective teeth 14 as shown in FIG. 5F. While FIG. 5F appears similarto FIG. 5E because it is a plan view it should be kept in mind that thewinding needle 12 is in raised position in FIG. 5E and in loweredposition in FIG. 5F.

The back and forth motion of winding needle 12 from one side of the rowof teeth 12 to the other is effected by the first motor 24 swinging orrotating the swing plate 20 through a prescribed arc. The motion ofwinding needle 12 up and down in the second axial direction isimplemented by needle carrier motor 19a extending and retracting theneedle mounting arm 18 and therefore raising and lowering the windingneedle 12 relative to the row of teeth 14. Throughout such steps, thewinding needle is always in alignment with a slot for laying wire in theslot but without passing through the slot.

The clamp block 45b is then released and clamp block elements 45a and45b on opposite sides of stack 15 are temporarily both in the openposition as shown in FIG. 5G. With,the clamp blocks both in openposition the row of teeth 14 is then translated back to the leftrelative to the winding needle and clamp blocks which in the case of theannular configuration stack is effected by clockwise rotation of stack15 within the rotating frame or insert 28 of stack mounting block 30. Inthe event a linear stack is wound the row of teeth is simply translatedin the desired direction. Movement of the stack 15 and row of teeth 14to the left relative to winding needle 12 and clamp blocks 45a and 45bis illustrated in FIG. 5H.

The opposite clamp block element 45a is then actuated to the clampingposition by fourth motor 48 and clamp yoke 40 pushing and clamping thewinding wire 11 against the other side of the row of teeth 14. Asequence of steps then follows with clamp block element 45b in clampingposition comprising raising the winding needle 12 from a positionadjacent the base of the row of teeth to a position above the row ofteeth; moving the winding needle from the position on the other side ofthe row of teeth to a position on the initial side of the row of teeth:and lowering the winding needle once again to a position adjacent to thebase of the row of teeth so that the winding wire is again seated in aslot between teeth 14 of the row. However, at no time does the windingneedle pass through a slot.

Clamp block element 45b is then released and while the clamping members45a and 45b on opposite sides of the row of teeth are both in openposition the step follows of again moving the stack 15 and row of teeth14 this time to the right relative to the winding needle 12 to anotherlocation for further winding operations.

It is apparent from the sequence of steps set forth above that in themethod of stack winding according to the present invention the windingneedle "dances" up and down and back and forth over the row of teeth inalignment with a slot seating the winding wire in slots betweenrespective teeth of the stack. During the "dance" of the winding needle,the clamping blocks or elements alternately clamp the winding wireagainst one side of the row of teeth and then the other side by means ofthe pliant surface while the winding needle moves up and down and backand forth over the row of teeth. Of equal importance, the clampingblocks or elements on opposite sides of the stack release the pliantsurfaces from either side of the row of teeth and both remain in openposition while the stack and row of teeth move relative to the windingneedle and clamp blocks or elements to different slot and teethlocations of the stack. A diagrammatic and perspective representation ofthe "dance" of the winding needle according to the method of the presentinvention is illustrated in FIG. 6.

In FIG. 6 the sequence of steps according to the stack winding methodare renumbered 1 through 12 for convenience. In step 1 the stack isrotated to place the row of teeth in positon relative to the stackwinding needle at a first location. At the end of step 1 the clampingmember or block on the one side or initial side of the row of teeth isactuated into the clamping position against the winding wire and row ofteeth represented in the diagram by numeral 2. The winding needle thenrises above the row of teeth represented by line 3, traverses over oracross the row of teeth represented by line 4, and lowers on the otherside to the base of a slot of the row of teeth represented by line 5. Bythis sequence of steps the winding wire is seated in the base of a slotat the desired first location. The first clamping block or member on theinitial side of the row of teeth is then released represented by thecorner designation numeral 6 and while the clamps on both sides of therow of teeth are in open position the stack is rotated or translatedrepresented by line 7 to a position relative to the winding wire at asecond location. After each stack shift, a slot in the row of teeth isaligned with the winding needle.

At the second location the clamp or clamping member on the other side ofthe row of teeth, that is the second clamping member, is actuated to theclamp position clamping and holding the winding wire against theopposite side of the row of teeth which step is represented by thecorner designation numeral 8. While the second clamping member on theopposite side of the row of teeth is in clamp position the windingneedle rises from a position at the base of the slot and teeth at thesecond location to a raised position above the row of teeth representedby line 9. The winding needle then traverses or translates across andover the row of teeth represented by line 10, and then lowers on theinitial side to a position at the base of the slot at the secondlocation represented by line 11.

The second clamp on the opposite side of the row of teeth is thenreleased and while both clamps are in open position the stack may berotated or translated placing the row of teeth relative to the windingneedle in another location for further winding operations.

A critical feature of the method according to the present invention isthe interrelationship of the "dance" of the winding needle and theactuation of the pliant surface clamps or clamping blocks between theclamp position and open position. Referring to FIG. 6, during steps 3,4, and 5 the winding wire is clamped against the initial side of the rowof teeth by the clamping block on that side. During steps 9, 10, and 11the winding wire is clamped against the opposite side of the row ofteeth. During steps 1 and 7 both clamping blocks on either side of therow of teeth are in open position.

A sequential listing of each of the steps corresponding to FIG. 6 andthe corresponding state of the stack winding elements is found in TableI. During most of the steps the stack and row of teeth are stopped andin fixed position. However, at appropriate steps in the method the stackor row of teeth typically alternately shift left and then right orrotate clockwise and then counterclockwise. The alternate right and leftshifts or clockwise and counterclockwise rotational shifts alternatelyposition the stack and row of teeth relative to the winding needle forplacing multiple turns of wire in the desired copper densitydistributions such as the tapered distributions required for angleresolver transformer windings.

It will be readily apparent to one skilled in the art that the fourmotors actuating and driving the moving elements of the stack windingapparatus and method may be automatically controlled in desiredprogrammed sequences using, for example, a microprocessor. In this waycomplex winding distributions may be achieved and automated inaccordance with the apparatus and method of the present invention.Furthermore, a variety of other hardware arrangements may be used forachieving relative motion between the winding needle and stack in threecoordinate axis directions.

While the invention has been described with reference to particularexample embodiments, it is intended to cover all variations andequivalents within the scope of the following claims.

                  TABLE I                                                         ______________________________________                                              WIRE GUIDE                                                                    NEEDLE      CLAMP #1          CLAMP #2                                  STEP  POSITION    POSITION   STACK  POSITION                                  ______________________________________                                        1     Down        Open       Shift  Open                                                                   Right                                            2     Down        Clamp      Stop   Open                                      3     Up          Clamp      Stop   Open                                      4     Traverse    Clamp      Stop   Open                                      5     Down        Clamp      Stop   Open                                      6     Down        Open       Stop   Open                                      7     Down        Open       Shift Left                                                                           Open                                      8     Down        Open       Stop   Clamp                                     9     Up          Open       Stop   Clamp                                     10    Traverse    Open       Stop   Clamp                                     11    Down        Open       Stop   Clamp                                     12    Down        Open       Shift  Open                                                                   Right                                            ______________________________________                                    

I claim:
 1. Stack winding apparatus for winding wire around selectedteeth of a toothed or slotted stack having at least a row of teethcomprising:wire feed winding guide means for guiding wire aroundselected teeth of the stack; guide mounting means operatively supportingsaid winding guide means for movement in at least two coordinate axisdirections relative to the stack to be wound; stack mounting means foroperatively supporting a toothed stack for movement relative to saidwinding guide means and guide mounting means in a third coordinate axisdirection along a row of teeth; first motor means operatively coupled tosaid guide mounting means for moving said winding guide means back andforth in a first coordinate axis direction across the stack of eitherside of the row of teeth; second motor means operatively coupled to saidguide mounting means for moving said winding guide means up and down ina second coordinate axis direction substantially parallel with the teethand slots of the stack; third motor means operatively arranged formoving a stack mounted in the stack mounting means relative to thewinding guide means in a third coordinate axis direction along a row ofteeth of the stack; clamp means operatively positioned on either side ofthe row of teeth, said clamp means formed with pliant bearing surfacesin the direction facing said teeth; clamp mounting means operativelymounting said clamp means for movement toward and away from said row ofteeth between a clamp position and an open position, in which clampposition the pliant bearing surface of said clamp means bears against aportion of one side of the row of teeth conforming to the surface of anywinding already formed around selected teeth whereby the winding wire isheld in place while the winding guide means moves relative to said stackin said first and second coordinate axis directions back and forthacross the row of teeth, and up and down parallel to the teeth andslots, and in which open position the stack moves in the thirdcoordinate axis direction along the row of teeth relative to saidwinding guide means for winding wire around teeth and through slots atfurther locations; fourth motor means operatively coupled to said clampmounting means for moving said clamp means alternately between saidclamp and open positions.
 2. The stack winding apparatus of claim 1wherein the guide mounting means comprises an axle and a swing platemounted on said axle for rotational motion through a prescribed arc anda translating guide carrier mounted on the swing plate for impartingtranslational motion relative to said swing plate.
 3. The stack windingapparatus of claim 2 wherein said guide carrier comprises a guidemounting arm extending from said guide carrier beyond a side of theswing plate, said winding guide means mounted at the end of said armaway from the guide carrier and swing plate whereby rotational motion ofsaid swing plate through the prescribed arc imparts back and forthmotion to said guide means substantially along a first coordinate axisdirection and wherein said guide carrier is constructed and operativelyarranged for extension and retraction of said guide arm for imparting upand down motion to said winding guide means along a second coordinateaxis direction.
 4. The stack winding apparatus of claim 3 furthercomprising gear and rack means operatively coupling said first motormeans to said swing plate for imparting rotational motion over aspecified arc.
 5. The stack winding apparatus of claim 3 wherein saidstack mounting means comprises a mounting plate ring for mounting stacksof annular configuration, said mounting plate ring formed with a gearedperiphery and further comprising worm gear means engaging said gearedperiphery, said third motor means operatively coupled to said worm gearmeans for rotating the stack and thereby translating the row of teethrelative to said winding guide means.
 6. The appararus of claim 3wherein said clamp mounting means comprises clamp yoke means formedcoaxially around said swing plate axle for independent rotationalmovement relative to said axle, said clamp yoke means comprising firstand second yoke arms extending on either side of said axle and swingplate, and first and second clamp mounting arms extending from saidrespective first and second yoke arms in a direction parallel with theneedle mounting arm, said clamp means comprising first and second flatpliable surface pushers mounted respectively on said first and secondclamp mounting arms, said fourth motor means operatively coupled to saidyoke means for imparting rotational motion whereby said pliant surfacepushers alternately extend forward and back between said clamp positionand said open position.
 7. The stack winding apparatus of claim 6wherein each said first and second pliable surface pusher comprisesspaced apart adjacent pushing elements for engaging in the clampposition the side of a row of teeth at different tooth locations.
 8. Thestack winding apparatus of claim 6 wherein said stack mounting meanscomprises a stack mounting plate for mounting said stack with a row ofteeth between said pliant surface pushers and generally below thewinding needle means supported on said needle mounting arm.
 9. Stackwinding apparatus for winding wire around selected teeth of a toothed orslotted stack having at least a row of teeth comprising:wire feedwinding needle means for feeding and winding wire around selected teethof the stack; needle mounting means operatively supporting said windingneedle means for movement relative to the stack back and forth over therow of teeth; stack mounting means for operatively supporting a toothedstack for lateral movement relative to said winding needle means andneedle mounting means; said needle mounting means and stack mountingmeans constructed and arranged for movement relative to each other ofthe winding needle means and the row of teeth of a stack to be wound, inthree substantially perpendicular coordinate axis directions; means formoving said winding needle means and the row of teeth of a stack to bewound in said three coordinate axis directions relative to each otherfor laying wire in the slots without the winding needle means passingthrough said slots; wire holding clamp means operatively positioned oneither side of the row of teeth of a toothed or slotted stack, each saidclamp means formed with a substantially flat pliant bearing surface inthe direction facing said teeth; clamp mounting means operativelymounting each said clamp means for movement toward and away from saidrow of teeth between a stationary clamp position pushing against theside of the row of teeth for holding winding wire in place and an openposition, in which stationary clamp position the pliant bearing surfaceof said clamp means bears against a portion of one side of the row ofteeth conforming to the surface of any winding already formed aroundselect teeth so that the winding wire is held in place while the needlemounting means moves relative to the stack mounting means back and forthover the row of teeth.
 10. The stack winding apparatus of claim 9wherein each clamp means comprises first and second flat pliable surfacepushers mounted on the clamp mounting means, said first and secondpliable surface pushers being spaced apart from each other for engagingin the clamp position the side of a row of teeth at different toothlocations.
 11. The stack winding apparatus of claim 9 wherein the clampmounting means comprises clamp yoke means formed with first and secondyoke arms and clamp motor means for extending and retracting the yokearms and flat pliable surface pushers between the clamp position andopen position.
 12. Apparatus for winding wire around selected teeth of atoothed or slotted stack having a row of teeth, including wire feedwinding guide means for guiding wire around selected teeth of a toothedor slotted stack, and stack mounting means constructed and arranged foroperatively mounting a toothed or slotted stack relative to the wirefeed winding guide means, the improvement comprising:wire holding clampmeans operatively positioned on either side of a row of teeth of atoothed or slotted stack mounted on the stack mounting means, each saidclamp means formed with a substantially flat pliant bearing surface inthe direction facing said teeth; clamp mounting means operativelymounting each said clamp means for movement toward and away from saidrow of teeth between a stationary clamp position pushing against theside of the row of teeth for holding winding wire in place and an openposition, in which stationary clamp position the pliant bearing surfaceof the clamp means bears against a portion of one side of the row ofteeth conforming to the surface of any winding already formed aroundselected teeth so that the winding wire is held in place against theside of the row of teeth while the wire feed winding guide means isguiding wire; and clamp motor means operatively coupled to the clampmounting means for moving said clamp means alternatively between thestationary clamp position and the open position to facilitate selectivewinding of wire around selected teeth.
 13. The apparatus of claim 12wherein each said clamp means comprise first and second spaced apartpliable surface pushers mounted on the clamp mounting means for engagingin the clamp position the side of a row of teeth at different toothlocations.
 14. The apparatus of claim 13 wherein said clamp mountingmeans comprises clamp yoke means having first and second yoke arms, saidclamp motor means being operatively coupled to the clamp yoke means formoving the pliable surface pushers between the stationary clamp positionand the open position.